Abeam of monochromatic light is diffracted by a slit of width 0.580 mm. the diffraction pattern forms on a wall 1.56 m beyond the slit. the width of the central maximum is 2.05 mm.
calculate the wavelength of the light.

 λ = 381 nm

Explanation:

given,

width of slit,a = 0.580 x 10⁻³ m

distance of the screen from the slit, D = 1.56 m

width of central maximum,y = 2.05 x 10⁻³ m

Distance of the edge of central maximum from center of the central maximum y ‘ = y/ 2  

                      Y ‘ = 1.025 x  10⁻³ m

for first maximum

d sin θ = λ

sin θ = tan θ = y'/D

 λ = 381 x 10⁻⁹ m

 λ = 381 nm

wavelength of light is equal to 381 nm.

the answer is 12 as i may remember

: )